[Cake] [PATCH iproute2 net-next] Add support for cake qdisc

Dave Taht dave.taht at gmail.com
Sun Dec 3 17:42:47 EST 2017


sch_cake is intended to squeeze the most bandwidth and latency out of even
the slowest ISP links and routers, while presenting an API simple enough
that even an ISP can configure it.

Example of use on a cable ISP uplink:

tc qdisc add dev eth0 cake bandwidth 20Mbit nat docsis ack-filter

To shape a cable download link (ifb and tc-mirred setup elided)

tc qdisc add dev ifb0 cake bandwidth 200mbit nat docsis ingress wash besteffort

Cake is filled with:

* A hybrid Codel/Blue AQM algorithm, "Cobalt", tied to an FQ_Codel
  derived Flow Queuing system, which autoconfigures based on the bandwidth.
* A novel "triple-isolate" mode (the default) which balances per-host
  and per-flow FQ even through NAT.
* An deficit based shaper, that can also be used in an unlimited mode.
* 8 way set associative hashing to reduce flow collisions to a minimum.
* A reasonable interpretation of various diffserv latency/loss tradeoffs.
* Support for zeroing diffserv markings for entering and exiting traffic.
* Support for interacting well with Docsis 3.0 shaper framing.
* Support for DSL framing types and shapers.
* (New) Support for ack filtering.
* Extensive statistics for measuring, loss, ecn markings, latency variation.

There are some features still considered experimental, notably the
ingress_autorate bandwidth estimator and cobalt itself.

Various versions baking have been available as an out of tree build for
kernel versions going back to 3.10, as the embedded router world has been
running a few years behind mainline Linux. A stable version has been
generally available on lede-17.01 and later.

sch_cake replaces a combination of iptables, tc filter, htb and fq_codel
in the sqm-scripts, with sane defaults and vastly simpler configuration.

Cake's principal author is Jonathan Morton, with contributions from
Kevin Darbyshire-Bryant, Toke Høiland-Jørgensen, Sebastian Moeller,
Ryan Mounce, Guido Sarducci, Dean Scarff, Nils Andreas Svee, Dave Täht,
and Loganaden Velvindron.

Testing from Pete Heist, Georgios Amanakis, and the many other members of
the cake at lists.bufferbloat.net mailing list.

Signed-off-by: Dave Taht <dave.taht at gmail.com>
---
 man/man8/tc-cake.8 | 678 ++++++++++++++++++++++++++++++++++++++++++++++
 tc/Makefile        |   1 +
 tc/q_cake.c        | 771 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 1450 insertions(+)
 create mode 100644 man/man8/tc-cake.8
 create mode 100644 tc/q_cake.c

diff --git a/man/man8/tc-cake.8 b/man/man8/tc-cake.8
new file mode 100644
index 0000000..788e046
--- /dev/null
+++ b/man/man8/tc-cake.8
@@ -0,0 +1,678 @@
+.TH CAKE 8 "23 November 2017" "iproute2" "Linux"
+.SH NAME
+CAKE \- COMMON Applications Kept Enhanced (CAKE)
+.SH SYNOPSIS
+.B tc qdisc ... cake
+.br
+[
+.BR bandwidth
+RATE |
+.BR unlimited*
+|
+.BR autorate_ingress
+]
+.br
+[
+.BR rtt
+TIME |
+.BR datacentre
+|
+.BR lan
+|
+.BR metro
+|
+.BR regional
+|
+.BR internet*
+|
+.BR oceanic
+|
+.BR satellite
+|
+.BR interplanetary
+]
+.br
+[
+.BR besteffort
+|
+.BR diffserv8
+|
+.BR diffserv4
+|
+.BR diffserv-llt
+|
+.BR diffserv3*
+]
+.br
+[
+.BR flowblind
+|
+.BR srchost
+|
+.BR dsthost
+|
+.BR hosts
+|
+.BR flows
+|
+.BR dual-srchost
+|
+.BR dual-dsthost
+|
+.BR triple-isolate*
+]
+.br
+[
+.BR nat
+|
+.BR nonat*
+]
+.br
+[
+.BR wash
+|
+.BR nowash*
+]
+.br
+[
+.BR ack-filter
+|
+.BR ack-filter-aggressive
+|
+.BR no-ack-filter*
+]
+.br
+[
+.BR memlimit
+LIMIT ]
+.br
+[
+.BR ptm
+|
+.BR atm
+|
+.BR noatm*
+]
+.br
+[
+.BR overhead
+N |
+.BR conservative
+|
+.BR raw*
+]
+.br
+[
+.BR mpu
+N ]
+.br
+[
+.BR ingress
+|
+.BR egress*
+]
+.br
+(* marks defaults)
+
+
+.SH DESCRIPTION
+CAKE (Common Applications Kept Enhanced) is a shaping-capable queue discipline
+which uses both AQM and FQ.  It combines COBALT, which is an AQM algorithm
+combining Codel and BLUE, a shaper which operates in deficit mode, and a variant
+of DRR++ for flow isolation.  8-way set-associative hashing is used to virtually
+eliminate hash collisions.  Priority queuing is available through a simplified
+diffserv implementation.  Overhead compensation for various encapsulation
+schemes is tightly integrated.
+
+All settings are optional; the default settings are chosen to be sensible in
+most common deployments.  Most people will only need to set the
+.B bandwidth
+parameter to get useful results, but reading the
+.B Overhead Compensation
+and
+.B Round Trip Time
+sections is strongly encouraged.
+
+.SH SHAPER PARAMETERS
+CAKE uses a deficit-mode shaper, which does not exhibit the initial burst
+typical of token-bucket shapers.  It will automatically burst precisely as much
+as required to maintain the configured throughput.  As such, it is very
+straightforward to configure.
+.PP
+.B unlimited
+(default)
+.br
+	No limit on the bandwidth.
+.PP
+.B bandwidth
+RATE
+.br
+	Set the shaper bandwidth.  See
+.BR tc(8)
+or examples below for details of the RATE value.
+.PP
+.B autorate_ingress
+.br
+	Automatic capacity estimation based on traffic arriving at this qdisc.
+This is most likely to be useful with cellular links, which tend to change
+quality randomly.  A
+.B bandwidth
+parameter can be used in conjunction to specify an initial estimate.  The shaper
+will periodically be set to a bandwidth slightly below the estimated rate.  This
+estimator cannot estimate the bandwidth of links downstream of itself.
+
+.SH OVERHEAD COMPENSATION PARAMETERS
+The size of each packet on the wire may differ from that seen by Linux.  The
+following parameters allow CAKE to compensate for this difference by internally
+considering each packet to be bigger than Linux informs it.  To assist users who
+are not expert network engineers, keywords have been provided to represent a
+number of common link technologies.
+
+.SS	Manual Overhead Specification
+.B overhead
+BYTES
+.br
+	Adds BYTES to the size of each packet.  BYTES may be negative; values
+between -64 and 256 (inclusive) are accepted.
+.PP
+.B mpu
+BYTES
+.br
+	Rounds each packet (including overhead) up to a minimum length
+BYTES. BYTES may not be negative; values between 0 and 256 (inclusive)
+are accepted.
+.PP
+.B atm
+.br
+	Compensates for ATM cell framing, which is normally found on ADSL links.
+This is performed after the
+.B overhead
+parameter above.  ATM uses fixed 53-byte cells, each of which can carry 48 bytes
+payload.
+.PP
+.B ptm
+.br
+	Compensates for PTM encoding, which is normally found on VDSL2 links and
+uses a 64b/65b encoding scheme. It is even more efficient to simply
+derate the specified shaper bandwidth by a factor of 64/65 or 0.984. See
+ITU G.992.3 Annex N and IEEE 802.3 Section 61.3 for details.
+.PP
+.B noatm
+.br
+	Disables ATM and PTM compensation.
+
+.SS	Failsafe Overhead Keywords
+These two keywords are provided for quick-and-dirty setup.  Use them if you
+can't be bothered to read the rest of this section.
+.PP
+.B raw
+(default)
+.br
+	Turns off all overhead compensation in CAKE.  The packet size reported
+by Linux will be used directly.
+.PP
+	Other overhead keywords may be added after "raw".  The effect of this is
+to make the overhead compensation operate relative to the reported packet size,
+not the underlying IP packet size.
+.PP
+.B conservative
+.br
+	Compensates for more overhead than is likely to occur on any
+widely-deployed link technology.
+.br
+	Equivalent to
+.B overhead 48 atm.
+
+.SS ADSL Overhead Keywords
+Most ADSL modems have a way to check which framing scheme is in use.  Often this
+is also specified in the settings document provided by the ISP.  The keywords in
+this section are intended to correspond with these sources of information.  All
+of them implicitly set the
+.B atm
+flag.
+.PP
+.B pppoa-vcmux
+.br
+	Equivalent to
+.B overhead 10 atm
+.PP
+.B pppoa-llc
+.br
+	Equivalent to
+.B overhead 14 atm
+.PP
+.B pppoe-vcmux
+.br
+	Equivalent to
+.B overhead 32 atm
+.PP
+.B pppoe-llcsnap
+.br
+	Equivalent to
+.B overhead 40 atm
+.PP
+.B bridged-vcmux
+.br
+	Equivalent to
+.B overhead 24 atm
+.PP
+.B bridged-llcsnap
+.br
+	Equivalent to
+.B overhead 32 atm
+.PP
+.B ipoa-vcmux
+.br
+	Equivalent to
+.B overhead 8 atm
+.PP
+.B ipoa-llcsnap
+.br
+	Equivalent to
+.B overhead 16 atm
+.PP
+See also the Ethernet Correction Factors section below.
+
+.SS VDSL2 Overhead Keywords
+ATM was dropped from VDSL2 in favour of PTM, which is a much more
+straightforward framing scheme.  Some ISPs retained PPPoE for compatibility with
+their existing back-end systems.
+.PP
+.B pppoe-ptm
+.br
+	Equivalent to
+.B overhead 30 ptm
+
+.br
+	PPPoE: 2B PPP + 6B PPPoE +
+.br
+	ETHERNET: 6B dest MAC + 6B src MAC + 2B ethertype + 4B Frame Check Sequence +
+.br
+	PTM: 1B Start of Frame (S) + 1B End of Frame (Ck) + 2B TC-CRC (PTM-FCS)
+.br
+.PP
+.B bridged-ptm
+.br
+	Equivalent to
+.B overhead 22 ptm
+.br
+	ETHERNET: 6B dest MAC + 6B src MAC + 2B ethertype + 4B Frame Check Sequence +
+.br
+	PTM: 1B Start of Frame (S) + 1B End of Frame (Ck) + 2B TC-CRC (PTM-FCS)
+.br
+.PP
+See also the Ethernet Correction Factors section below.
+
+.SS DOCSIS Cable Overhead Keyword
+DOCSIS is the universal standard for providing Internet service over cable-TV
+infrastructure.
+
+In this case, the actual on-wire overhead is less important than the packet size
+the head-end equipment uses for shaping and metering.  This is specified to be
+an Ethernet frame including the CRC (aka FCS).
+.PP
+.B docsis
+.br
+	Equivalent to
+.B overhead 18 mpu 64 noatm
+
+.SS Ethernet Overhead Keywords
+.PP
+.B ethernet
+.br
+	Accounts for Ethernet's preamble, inter-frame gap, and Frame Check
+Sequence.  Use this keyword when the bottleneck being shaped for is an
+actual Ethernet cable.
+.br
+	Equivalent to
+.B overhead 38 mpu 84 noatm
+.PP
+.B ether-vlan
+.br
+	Adds 4 bytes to the overhead compensation, accounting for an IEEE 802.1Q
+VLAN header appended to the Ethernet frame header.  NB: Some ISPs use one or
+even two of these within PPPoE; this keyword may be repeated as necessary to
+express this.
+
+.SH ROUND TRIP TIME PARAMETERS
+Active Queue Management (AQM) consists of embedding congestion signals in the
+packet flow, which receivers use to instruct senders to slow down when the queue
+is persistently occupied.  CAKE uses ECN signalling when available, and packet
+drops otherwise, according to a combination of the Codel and BLUE AQM algorithms
+called COBALT.
+
+Very short latencies require a very rapid AQM response to adequately control
+latency.  However, such a rapid response tends to impair throughput when the
+actual RTT is relatively long.  CAKE allows specifying the RTT it assumes for
+tuning various parameters.  Actual RTTs within an order of magnitude of this
+will generally work well for both throughput and latency management.
+
+At the 'lan' setting and below, the time constants are similar in magnitude to
+the jitter in the Linux kernel itself, so congestion might be signalled
+prematurely. The flows will then become sparse and total throughput reduced,
+leaving little or no back-pressure for the fairness logic to work against. Use
+the "metro" setting for local lans unless you have a custom kernel.
+.PP
+.B rtt
+TIME
+.br
+	Manually specify an RTT.
+.PP
+.B datacentre
+.br
+	For extremely high-performance 10GigE+ networks only.  Equivalent to
+.B rtt 100us.
+.PP
+.B lan
+.br
+	For pure Ethernet (not Wi-Fi) networks, at home or in the office.  Don't
+use this when shaping for an Internet access link.  Equivalent to
+.B rtt 1ms.
+.PP
+.B metro
+.br
+	For traffic mostly within a single city.  Equivalent to
+.B rtt 10ms.
+.PP
+.B regional
+.br
+	For traffic mostly within a European-sized country.  Equivalent to
+.B rtt 30ms.
+.PP
+.B internet
+(default)
+.br
+	This is suitable for most Internet traffic.  Equivalent to
+.B rtt 100ms.
+.PP
+.B oceanic
+.br
+	For Internet traffic with generally above-average latency, such as that
+suffered by Australasian residents.  Equivalent to
+.B rtt 300ms.
+.PP
+.B satellite
+.br
+	For traffic via geostationary satellites.  Equivalent to
+.B rtt 1000ms.
+.PP
+.B interplanetary
+.br
+	So named because Jupiter is about 1 light-hour from Earth.  Use this to
+(almost) completely disable AQM actions.  Equivalent to
+.B rtt 3600s.
+
+.SH FLOW ISOLATION PARAMETERS
+With flow isolation enabled, CAKE places packets from different flows into
+different queues, each of which carries its own AQM state.  Packets from each
+queue are then delivered fairly, according to a DRR++ algorithm which minimises
+latency for "sparse" flows.  CAKE uses a set-associative hashing algorithm to
+minimise flow collisions.
+
+These keywords specify whether fairness based on source address, destination
+address, individual flows, or any combination of those is desired.
+.PP
+.B flowblind
+.br
+	Disables flow isolation; all traffic passes through a single queue for
+each tin.
+.PP
+.B srchost
+.br
+	Flows are defined only by source address.  Could be useful on the egress
+path of an ISP backhaul.
+.PP
+.B dsthost
+.br
+	Flows are defined only by destination address.  Could be useful on the
+ingress path of an ISP backhaul.
+.PP
+.B hosts
+.br
+	Flows are defined by source-destination host pairs.  This is host
+isolation, rather than flow isolation.
+.PP
+.B flows
+.br
+	Flows are defined by the entire 5-tuple of source address, destination
+address, transport protocol, source port and destination port.  This is the type
+of flow isolation performed by SFQ and fq_codel.
+.PP
+.B dual-srchost
+.br
+	Flows are defined by the 5-tuple, and fairness is applied first over
+source addresses, then over individual flows.  Good for use on egress traffic
+from a LAN to the internet, where it'll prevent any one LAN host from
+monopolising the uplink, regardless of the number of flows they use.
+.PP
+.B dual-dsthost
+.br
+	Flows are defined by the 5-tuple, and fairness is applied first over
+destination addresses, then over individual flows.  Good for use on ingress
+traffic to a LAN from the internet, where it'll prevent any one LAN host from
+monopolising the downlink, regardless of the number of flows they use.
+.PP
+.B triple-isolate
+(default)
+.br
+	Flows are defined by the 5-tuple, and fairness is applied over source
+*and* destination addresses intelligently (ie. not merely by host-pairs), and
+also over individual flows.  Use this if you're not certain whether to use
+dual-srchost or dual-dsthost; it'll do both jobs at once, preventing any one
+host on *either* side of the link from monopolising it with a large number of
+flows.
+.PP
+.B nat
+.br
+	Instructs Cake to perform a NAT lookup before applying flow-isolation
+rules, to determine the true addresses and port numbers of the packet, to
+improve fairness between hosts "inside" the NAT.  This has no practical effect
+in "flowblind" or "flows" modes, or if NAT is performed on a different host.
+.PP
+.B nonat
+(default)
+.br
+	Cake will not perform a NAT lookup.  Flow isolation will be performed
+using the addresses and port numbers directly visible to the interface Cake is
+attached to.
+
+.SH PRIORITY QUEUE PARAMETERS
+CAKE can divide traffic into "tins" based on the Diffserv field.  Each tin has
+its own independent set of flow-isolation queues, and is serviced based on a WRR
+algorithm.  To avoid perverse Diffserv marking incentives, tin weights have a
+"priority sharing" value when bandwidth used by that tin is below a threshold,
+and a lower "bandwidth sharing" value when above.  Bandwidth is compared against
+the threshold using the same algorithm as the deficit-mode shaper.
+
+Detailed customisation of tin parameters is not provided.  The following presets
+perform all necessary tuning, relative to the current shaper bandwidth and RTT
+settings.
+.PP
+.B besteffort
+.br
+	Disables priority queuing by placing all traffic in one tin.
+.PP
+.B precedence
+.br
+	Enables legacy interpretation of TOS "Precedence" field.  Use of this
+preset on the modern Internet is firmly discouraged.
+.PP
+.B diffserv-llt
+.br
+	Provides a "Latency-Loss Tradeoff" implementation with five tins:
+.br
+		Low Loss (TOS1, TOS2), 100% threshold, increased Codel target.
+.br
+		Best Effort (general), 100% threshold, normal Codel target & interval.
+.br
+		Low Latency (TOS4, TOS5, VA, EF), 100% threshold, reduced Codel interval.
+.br
+		Bulk (CS1), 6.25% threshold, normal Codel target & interval.
+.br
+		Net Control (CS6, CS7), 6.25% threshold, increased Codel target & interval.
+.PP
+.B diffserv4
+.br
+	Provides a general-purpose Diffserv implementation with four tins:
+.br
+		Bulk (CS1), 6.25% threshold, generally low priority.
+.br
+		Best Effort (general), 100% threshold.
+.br
+		Video (AF4x, AF3x, CS3, AF2x, CS2, TOS4, TOS1), 50% threshold.
+.br
+		Voice (CS7, CS6, EF, VA, CS5, CS4), 25% threshold.
+.PP
+.B diffserv3
+(default)
+.br
+	Provides a simple, general-purpose Diffserv implementation with three tins:
+.br
+		Bulk (CS1), 6.25% threshold, generally low priority.
+.br
+		Best Effort (general), 100% threshold.
+.br
+		Voice (CS7, CS6, EF, VA, TOS4), 25% threshold, reduced Codel interval.
+
+.SH OTHER PARAMETERS
+.B memlimit
+LIMIT
+.br
+	Limit the memory consumed by Cake to LIMIT bytes. Note that this does
+not translate directly to queue size (so do not size this based on bandwidth
+delay product considerations, but rather on worst case acceptable memory
+consumption), as there is some overhead in the data structures containing the
+packets, especially for small packets.
+
+	By default, the limit is calculated based on the bandwidth and RTT
+settings.
+
+.PP
+.B wash
+
+.br
+	Traffic entering your diffserv domain is frequently mis-marked in
+transit from the perspective of your network, and traffic exiting yours may be
+mis-marked from the perspective of the transiting provider.
+
+Apply the wash option to clear all extra diffserv (but not ECN bits), after
+priority queuing has taken place.
+
+If you are shaping inbound, and cannot trust the diffserv markings (as is the
+case for Comcast Cable, among others), it is best to use a single queue
+"besteffort" mode with wash.
+
+.SH EXAMPLES
+# tc qdisc delete root dev eth0
+.br
+# tc qdisc add root dev eth0 cake bandwidth 9500Kbit pppoe-ptm ether-vlan
+.br
+# tc -s qdisc show dev eth0
+.br
+qdisc cake 8007: root refcnt 6 bandwidth 9500Kbit diffserv3 triple-isolate rtt 100.0ms ptm overhead 34 via-ethernet total_overhead 34 hard_header_len 14
+ Sent 0 bytes 0 pkt (dropped 0, overlimits 0 requeues 0)
+ backlog 0b 0p requeues 0
+ memory used: 0b of 4Mb
+ capacity estimate: 9500Kbit
+.br
+                 Bulk   Best Effort      Voice
+.br
+  thresh     593744bit    9500Kbit    2375Kbit
+.br
+  target        30.6ms       5.0ms       7.6ms
+.br
+  interval     125.6ms     100.0ms     102.6ms
+.br
+  pk_delay         0us         0us         0us
+.br
+  av_delay         0us         0us         0us
+.br
+  sp_delay         0us         0us         0us
+.br
+  pkts               0           0           0
+.br
+  bytes              0           0           0
+.br
+  way_inds           0           0           0
+.br
+  way_miss           0           0           0
+.br
+  way_cols           0           0           0
+.br
+  drops              0           0           0
+.br
+  marks              0           0           0
+.br
+  ack_drop           0           0           0
+.br
+  sp_flows           0           0           0
+.br
+  bk_flows           0           0           0
+.br
+  un_flows           0           0           0
+.br
+  max_len            0           0           0
+.br
+
+After some use:
+.br
+# tc -s qdisc show dev eth0
+
+qdisc cake 8007: root refcnt 6 bandwidth 9500Kbit diffserv3 triple-isolate rtt 100.0ms ptm overhead 34 via-ethernet total_overhead 34 hard_header_len 14
+ Sent 110769306 bytes 313857 pkt (dropped 18, overlimits 741791 requeues 0)
+ backlog 0b 0p requeues 0
+ memory used: 110488b of 4Mb
+ capacity estimate: 9500Kbit
+.br
+                 Bulk   Best Effort      Voice
+.br
+  thresh     593744bit    9500Kbit    2375Kbit
+.br
+  target        30.6ms       5.0ms       7.6ms
+.br
+  interval     125.6ms     100.0ms     102.6ms
+.br
+  pk_delay      16.0ms       545us        15us
+.br
+  av_delay       2.4ms       161us         3us
+.br
+  sp_delay        59us         1us         1us
+.br
+  pkts           32866      195815       85194
+.br
+  bytes        8132614    69517496    33122156
+.br
+  way_inds           0       29208           0
+.br
+  way_miss           7         173          17
+.br
+  way_cols           0           0           0
+.br
+  drops             10           7           1
+.br
+  marks            217         692         300
+.br
+  ack_drop           0           0           0
+.br
+  sp_flows           0           0           0
+.br
+  bk_flows           0           0           1
+.br
+  un_flows           0           0           0
+.br
+  max_len         3028        3012        3028
+.br
+
+.SH SEE ALSO
+.BR tc (8),
+.BR tc-codel (8),
+.BR tc-fq_codel (8),
+.BR tc-red (8)
+
+.SH AUTHORS
+Cake's principal author is Jonathan Morton, with contributions from
+Kevin Darbyshire-Bryant, Toke Høiland-Jørgensen, Sebastian Moeller,
+Ryan Mounce, Guido Sarducci, Dean Scarff, Nils Andreas Svee, and Dave Täht.
+
+This manual page was written by Loganaden Velvindron. Please report corrections
+to the Linux Networking mailing list <netdev at vger.kernel.org>.
diff --git a/tc/Makefile b/tc/Makefile
index 3716dd6..69f50a6 100644
--- a/tc/Makefile
+++ b/tc/Makefile
@@ -64,6 +64,7 @@ TCMODULES += em_meta.o
 TCMODULES += q_mqprio.o
 TCMODULES += q_codel.o
 TCMODULES += q_fq_codel.o
+TCMODULES += q_cake.o
 TCMODULES += q_fq.o
 TCMODULES += q_pie.o
 TCMODULES += q_hhf.o
diff --git a/tc/q_cake.c b/tc/q_cake.c
new file mode 100644
index 0000000..b934bf7
--- /dev/null
+++ b/tc/q_cake.c
@@ -0,0 +1,771 @@
+/*
+ * Common Applications Kept Enhanced  --  CAKE
+ *
+ *  Copyright (C) 2014-2015 Jonathan Morton <chromatix99 at gmail.com>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions, and the following disclaimer,
+ *    without modification.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The names of the authors may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * Alternatively, provided that this notice is retained in full, this
+ * software may be distributed under the terms of the GNU General
+ * Public License ("GPL") version 2, in which case the provisions of the
+ * GPL apply INSTEAD OF those given above.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ */
+
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <syslog.h>
+#include <fcntl.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <string.h>
+
+#include "utils.h"
+#include "tc_util.h"
+
+static void explain(void)
+{
+	fprintf(stderr,
+"Usage: ... cake [ bandwidth RATE | unlimited* | autorate_ingress ]\n"
+"                [ rtt TIME | datacentre | lan | metro | regional |\n"
+"                  internet* | oceanic | satellite | interplanetary ]\n"
+"                [ besteffort | diffserv8 | diffserv4 | diffserv-llt |\n"
+"                  diffserv3* ]\n"
+"                [ flowblind | srchost | dsthost | hosts | flows |\n"
+"                  dual-srchost | dual-dsthost | triple-isolate* ]\n"
+"                [ nat | nonat* ]\n"
+"                [ wash | nowash * ]\n"
+"                [ ack-filter | ack-filter-aggressive | no-ack-filter * ]\n"
+"                [ memlimit LIMIT ]\n"
+"                [ ptm | atm | noatm* ] [ overhead N | conservative | raw* ]\n"
+"                [ mpu N ] [ ingress | egress* ]\n"
+"                (* marks defaults)\n");
+}
+
+static int cake_parse_opt(struct qdisc_util *qu, int argc, char **argv,
+			      struct nlmsghdr *n)
+{
+	int unlimited = 0;
+	unsigned bandwidth = 0;
+	unsigned interval = 0;
+	unsigned target = 0;
+	unsigned diffserv = 0;
+	unsigned memlimit = 0;
+	int  overhead = 0;
+	bool overhead_set = false;
+	bool overhead_override = false;
+	int mpu = 0;
+	int flowmode = -1;
+	int nat = -1;
+	int atm = -1;
+	int autorate = -1;
+	int wash = -1;
+	int ingress = -1;
+	int ack_filter = -1;
+	struct rtattr *tail;
+
+	while (argc > 0) {
+		if (strcmp(*argv, "bandwidth") == 0) {
+			NEXT_ARG();
+			if (get_rate(&bandwidth, *argv)) {
+				fprintf(stderr, "Illegal \"bandwidth\"\n");
+				return -1;
+			}
+			unlimited = 0;
+			autorate = 0;
+		} else if (strcmp(*argv, "unlimited") == 0) {
+			bandwidth = 0;
+			unlimited = 1;
+			autorate = 0;
+		} else if (strcmp(*argv, "autorate_ingress") == 0) {
+			autorate = 1;
+
+		} else if (strcmp(*argv, "rtt") == 0) {
+			NEXT_ARG();
+			if (get_time(&interval, *argv)) {
+				fprintf(stderr, "Illegal \"rtt\"\n");
+				return -1;
+			}
+			target = interval / 20;
+			if(!target)
+				target = 1;
+		} else if (strcmp(*argv, "datacentre") == 0) {
+			interval = 100;
+			target   =   5;
+		} else if (strcmp(*argv, "lan") == 0) {
+			interval = 1000;
+			target   =   50;
+		} else if (strcmp(*argv, "metro") == 0) {
+			interval = 10000;
+			target   =   500;
+		} else if (strcmp(*argv, "regional") == 0) {
+			interval = 30000;
+			target    = 1500;
+		} else if (strcmp(*argv, "internet") == 0) {
+			interval = 100000;
+			target   =   5000;
+		} else if (strcmp(*argv, "oceanic") == 0) {
+			interval = 300000;
+			target   =  15000;
+		} else if (strcmp(*argv, "satellite") == 0) {
+			interval = 1000000;
+			target   =   50000;
+		} else if (strcmp(*argv, "interplanetary") == 0) {
+			interval = 3600000000U;
+			target   =       5000;
+
+		} else if (strcmp(*argv, "besteffort") == 0) {
+			diffserv = 1;
+		} else if (strcmp(*argv, "precedence") == 0) {
+			diffserv = 2;
+		} else if (strcmp(*argv, "diffserv8") == 0) {
+			diffserv = 3;
+		} else if (strcmp(*argv, "diffserv4") == 0) {
+			diffserv = 4;
+		} else if (strcmp(*argv, "diffserv") == 0) {
+			diffserv = 4;
+		} else if (strcmp(*argv, "diffserv-llt") == 0) {
+			diffserv = 5;
+		} else if (strcmp(*argv, "diffserv3") == 0) {
+			diffserv = 6;
+
+		} else if (strcmp(*argv, "nowash") == 0) {
+			wash = 0;
+		} else if (strcmp(*argv, "wash") == 0) {
+			wash = 1;
+
+		} else if (strcmp(*argv, "flowblind") == 0) {
+			flowmode = 0;
+		} else if (strcmp(*argv, "srchost") == 0) {
+			flowmode = 1;
+		} else if (strcmp(*argv, "dsthost") == 0) {
+			flowmode = 2;
+		} else if (strcmp(*argv, "hosts") == 0) {
+			flowmode = 3;
+		} else if (strcmp(*argv, "flows") == 0) {
+			flowmode = 4;
+		} else if (strcmp(*argv, "dual-srchost") == 0) {
+			flowmode = 5;
+		} else if (strcmp(*argv, "dual-dsthost") == 0) {
+			flowmode = 6;
+		} else if (strcmp(*argv, "triple-isolate") == 0) {
+			flowmode = 7;
+
+		} else if (strcmp(*argv, "nat") == 0) {
+			nat = 1;
+		} else if (strcmp(*argv, "nonat") == 0) {
+			nat = 0;
+
+		} else if (strcmp(*argv, "ptm") == 0) {
+			atm = 2;
+		} else if (strcmp(*argv, "atm") == 0) {
+			atm = 1;
+		} else if (strcmp(*argv, "noatm") == 0) {
+			atm = 0;
+
+		} else if (strcmp(*argv, "raw") == 0) {
+			atm = 0;
+			overhead = 0;
+			overhead_set = true;
+			overhead_override = true;
+		} else if (strcmp(*argv, "conservative") == 0) {
+			/*
+			 * Deliberately over-estimate overhead:
+			 * one whole ATM cell plus ATM framing.
+			 * A safe choice if the actual overhead is unknown.
+			 */
+			atm = 1;
+			overhead = 48;
+			overhead_set = true;
+
+		/* Various ADSL framing schemes, all over ATM cells */
+		} else if (strcmp(*argv, "ipoa-vcmux") == 0) {
+			atm = 1;
+			overhead += 8;
+			overhead_set = true;
+		} else if (strcmp(*argv, "ipoa-llcsnap") == 0) {
+			atm = 1;
+			overhead += 16;
+			overhead_set = true;
+		} else if (strcmp(*argv, "bridged-vcmux") == 0) {
+			atm = 1;
+			overhead += 24;
+			overhead_set = true;
+		} else if (strcmp(*argv, "bridged-llcsnap") == 0) {
+			atm = 1;
+			overhead += 32;
+			overhead_set = true;
+		} else if (strcmp(*argv, "pppoa-vcmux") == 0) {
+			atm = 1;
+			overhead += 10;
+			overhead_set = true;
+		} else if (strcmp(*argv, "pppoa-llc") == 0) {
+			atm = 1;
+			overhead += 14;
+			overhead_set = true;
+		} else if (strcmp(*argv, "pppoe-vcmux") == 0) {
+			atm = 1;
+			overhead += 32;
+			overhead_set = true;
+		} else if (strcmp(*argv, "pppoe-llcsnap") == 0) {
+			atm = 1;
+			overhead += 40;
+			overhead_set = true;
+
+		/* Typical VDSL2 framing schemes, both over PTM */
+		/* PTM has 64b/65b coding which absorbs some bandwidth */
+		} else if (strcmp(*argv, "pppoe-ptm") == 0) {
+			/* 2B PPP + 6B PPPoE + 6B dest MAC + 6B src MAC
+			 * + 2B ethertype + 4B Frame Check Sequence
+			 * + 1B Start of Frame (S) + 1B End of Frame (Ck)
+			 * + 2B TC-CRC (PTM-FCS) = 30B
+			 */
+			atm = 2;
+			overhead += 30;
+			overhead_set = true;
+		} else if (strcmp(*argv, "bridged-ptm") == 0) {
+			/* 6B dest MAC + 6B src MAC + 2B ethertype
+			 * + 4B Frame Check Sequence
+			 * + 1B Start of Frame (S) + 1B End of Frame (Ck)
+			 * + 2B TC-CRC (PTM-FCS) = 22B
+			 */
+			atm = 2;
+			overhead += 22;
+			overhead_set = true;
+
+		} else if (strcmp(*argv, "via-ethernet") == 0) {
+			/*
+			 * We used to use this flag to manually compensate for
+			 * Linux including the Ethernet header on Ethernet-type
+			 * interfaces, but not on IP-type interfaces.
+			 *
+			 * It is no longer needed, because Cake now adjusts for
+			 * that automatically, and is thus ignored.
+			 *
+			 * It would be deleted entirely, but it appears in the
+			 * stats output when the automatic compensation is
+			 * active.
+			 */
+
+		} else if (strcmp(*argv, "total_overhead") == 0) {
+			/*
+			 * This is the overhead cake accounts for; added here so
+			 * that cake's "tc -s qdisc" output can be directly
+			 * pasted into the tc command to instantate a new cake..
+			 */
+			NEXT_ARG();
+
+		} else if (strcmp(*argv, "hard_header_len") == 0) {
+			/*
+			 * This is the overhead the kernel automatically
+			 * accounted for; added here so that cake's "tc -s
+			 * qdisc" output can be directly pasted into the tc
+			 * command to instantiate a new cake..
+			 */
+			NEXT_ARG();
+
+		} else if (strcmp(*argv, "ethernet") == 0) {
+			/* ethernet pre-amble & interframe gap & FCS
+			 * you may need to add vlan tag */
+			overhead += 38;
+			overhead_set = true;
+			mpu = 84;
+
+		/* Additional Ethernet-related overhead used by some ISPs */
+		} else if (strcmp(*argv, "ether-vlan") == 0) {
+			/* 802.1q VLAN tag - may be repeated */
+			overhead += 4;
+			overhead_set = true;
+
+		/*
+		 * DOCSIS cable shapers account for Ethernet frame with FCS,
+		 * but not interframe gap or preamble.
+		 */
+		} else if (strcmp(*argv, "docsis") == 0) {
+			atm = 0;
+			overhead += 18;
+			overhead_set = true;
+			mpu = 64;
+
+		} else if (strcmp(*argv, "overhead") == 0) {
+			char* p = NULL;
+			NEXT_ARG();
+			overhead = strtol(*argv, &p, 10);
+			if(!p || *p || !*argv || overhead < -64 || overhead > 256) {
+				fprintf(stderr, "Illegal \"overhead\", valid range is -64 to 256\\n");
+				return -1;
+			}
+			overhead_set = true;
+
+		} else if (strcmp(*argv, "mpu") == 0) {
+			char* p = NULL;
+			NEXT_ARG();
+			mpu = strtol(*argv, &p, 10);
+			if(!p || *p || !*argv || mpu < 0 || mpu > 256) {
+				fprintf(stderr, "Illegal \"mpu\", valid range is 0 to 256\\n");
+				return -1;
+			}
+
+		} else if (strcmp(*argv, "ingress") == 0) {
+			ingress = 1;
+		} else if (strcmp(*argv, "egress") == 0) {
+			ingress = 0;
+
+		} else if (strcmp(*argv, "no-ack-filter") == 0) {
+			ack_filter = 0;
+		} else if (strcmp(*argv, "ack-filter") == 0) {
+			ack_filter = 0x0200;
+		} else if (strcmp(*argv, "ack-filter-aggressive") == 0) {
+			ack_filter = 0x0600;
+
+		} else if (strcmp(*argv, "memlimit") == 0) {
+			NEXT_ARG();
+			if(get_size(&memlimit, *argv)) {
+				fprintf(stderr, "Illegal value for \"memlimit\": \"%s\"\n", *argv);
+				return -1;
+			}
+
+		} else if (strcmp(*argv, "help") == 0) {
+			explain();
+			return -1;
+		} else {
+			fprintf(stderr, "What is \"%s\"?\n", *argv);
+			explain();
+			return -1;
+		}
+		argc--; argv++;
+	}
+
+	tail = NLMSG_TAIL(n);
+	addattr_l(n, 1024, TCA_OPTIONS, NULL, 0);
+	if (bandwidth || unlimited)
+		addattr_l(n, 1024, TCA_CAKE_BASE_RATE, &bandwidth, sizeof(bandwidth));
+	if (diffserv)
+		addattr_l(n, 1024, TCA_CAKE_DIFFSERV_MODE, &diffserv, sizeof(diffserv));
+	if (atm != -1)
+		addattr_l(n, 1024, TCA_CAKE_ATM, &atm, sizeof(atm));
+	if (flowmode != -1)
+		addattr_l(n, 1024, TCA_CAKE_FLOW_MODE, &flowmode, sizeof(flowmode));
+	if (overhead_set)
+		addattr_l(n, 1024, TCA_CAKE_OVERHEAD, &overhead, sizeof(overhead));
+	if (overhead_override) {
+		unsigned zero = 0;
+		addattr_l(n, 1024, TCA_CAKE_ETHERNET, &zero, sizeof(zero));
+	}
+	if (mpu > 0)
+		addattr_l(n, 1024, TCA_CAKE_MPU, &mpu, sizeof(mpu));
+	if (interval)
+		addattr_l(n, 1024, TCA_CAKE_RTT, &interval, sizeof(interval));
+	if (target)
+		addattr_l(n, 1024, TCA_CAKE_TARGET, &target, sizeof(target));
+	if (autorate != -1)
+		addattr_l(n, 1024, TCA_CAKE_AUTORATE, &autorate, sizeof(autorate));
+	if (memlimit)
+		addattr_l(n, 1024, TCA_CAKE_MEMORY, &memlimit, sizeof(memlimit));
+	if (nat != -1)
+		addattr_l(n, 1024, TCA_CAKE_NAT, &nat, sizeof(nat));
+	if (wash != -1)
+		addattr_l(n, 1024, TCA_CAKE_WASH, &wash, sizeof(wash));
+	if (ingress != -1)
+		addattr_l(n, 1024, TCA_CAKE_INGRESS, &ingress, sizeof(ingress));
+	if (ack_filter != -1)
+		addattr_l(n, 1024, TCA_CAKE_ACK_FILTER, &ack_filter, sizeof(ack_filter));
+
+	tail->rta_len = (void *) NLMSG_TAIL(n) - (void *) tail;
+	return 0;
+}
+
+
+static int cake_print_opt(struct qdisc_util *qu, FILE *f, struct rtattr *opt)
+{
+	struct rtattr *tb[TCA_CAKE_MAX + 1];
+	unsigned bandwidth = 0;
+	unsigned diffserv = 0;
+	unsigned flowmode = 0;
+	unsigned interval = 0;
+	unsigned memlimit = 0;
+	int overhead = 0;
+	int ethernet = 0;
+	int mpu = 0;
+	int atm = 0;
+	int nat = 0;
+	int autorate = 0;
+	int wash = 0;
+	int ingress = 0;
+	int ack_filter = 0;
+	SPRINT_BUF(b1);
+	SPRINT_BUF(b2);
+
+	if (opt == NULL)
+		return 0;
+
+	parse_rtattr_nested(tb, TCA_CAKE_MAX, opt);
+
+	if (tb[TCA_CAKE_BASE_RATE] &&
+	    RTA_PAYLOAD(tb[TCA_CAKE_BASE_RATE]) >= sizeof(__u32)) {
+		bandwidth = rta_getattr_u32(tb[TCA_CAKE_BASE_RATE]);
+		if(bandwidth)
+			fprintf(f, "bandwidth %s ", sprint_rate(bandwidth, b1));
+		else
+			fprintf(f, "unlimited ");
+	}
+	if (tb[TCA_CAKE_AUTORATE] &&
+		RTA_PAYLOAD(tb[TCA_CAKE_AUTORATE]) >= sizeof(__u32)) {
+		autorate = rta_getattr_u32(tb[TCA_CAKE_AUTORATE]);
+		if(autorate == 1)
+			fprintf(f, "autorate_ingress ");
+		else if(autorate)
+			fprintf(f, "(?autorate?) ");
+	}
+	if (tb[TCA_CAKE_DIFFSERV_MODE] &&
+	    RTA_PAYLOAD(tb[TCA_CAKE_DIFFSERV_MODE]) >= sizeof(__u32)) {
+		diffserv = rta_getattr_u32(tb[TCA_CAKE_DIFFSERV_MODE]);
+		switch(diffserv) {
+		case 1:
+			fprintf(f, "besteffort ");
+			break;
+		case 2:
+			fprintf(f, "precedence ");
+			break;
+		case 3:
+			fprintf(f, "diffserv8 ");
+			break;
+		case 4:
+			fprintf(f, "diffserv4 ");
+			break;
+		case 5:
+			fprintf(f, "diffserv-llt ");
+			break;
+		case 6:
+			fprintf(f, "diffserv3 ");
+			break;
+		default:
+			fprintf(f, "(?diffserv?) ");
+			break;
+		};
+	}
+	if (tb[TCA_CAKE_FLOW_MODE] &&
+	    RTA_PAYLOAD(tb[TCA_CAKE_FLOW_MODE]) >= sizeof(__u32)) {
+		flowmode = rta_getattr_u32(tb[TCA_CAKE_FLOW_MODE]);
+		nat = !!(flowmode & 64);
+		flowmode &= ~64;
+		switch(flowmode) {
+		case 0:
+			fprintf(f, "flowblind ");
+			break;
+		case 1:
+			fprintf(f, "srchost ");
+			break;
+		case 2:
+			fprintf(f, "dsthost ");
+			break;
+		case 3:
+			fprintf(f, "hosts ");
+			break;
+		case 4:
+			fprintf(f, "flows ");
+			break;
+		case 5:
+			fprintf(f, "dual-srchost ");
+			break;
+		case 6:
+			fprintf(f, "dual-dsthost ");
+			break;
+		case 7:
+			fprintf(f, "triple-isolate ");
+			break;
+		default:
+			fprintf(f, "(?flowmode?) ");
+			break;
+		};
+
+		if(nat)
+			fprintf(f, "nat ");
+	}
+	if (tb[TCA_CAKE_WASH] &&
+	    RTA_PAYLOAD(tb[TCA_CAKE_WASH]) >= sizeof(__u32)) {
+		wash = rta_getattr_u32(tb[TCA_CAKE_WASH]);
+	}
+	if (tb[TCA_CAKE_ATM] &&
+	    RTA_PAYLOAD(tb[TCA_CAKE_ATM]) >= sizeof(__u32)) {
+		atm = rta_getattr_u32(tb[TCA_CAKE_ATM]);
+	}
+	if (tb[TCA_CAKE_OVERHEAD] &&
+	    RTA_PAYLOAD(tb[TCA_CAKE_OVERHEAD]) >= sizeof(__u32)) {
+		overhead = rta_getattr_u32(tb[TCA_CAKE_OVERHEAD]);
+	}
+	if (tb[TCA_CAKE_MPU] &&
+	    RTA_PAYLOAD(tb[TCA_CAKE_MPU]) >= sizeof(__u32)) {
+		mpu = rta_getattr_u32(tb[TCA_CAKE_MPU]);
+	}
+	if (tb[TCA_CAKE_INGRESS] &&
+	    RTA_PAYLOAD(tb[TCA_CAKE_INGRESS]) >= sizeof(__u32)) {
+		ingress = rta_getattr_u32(tb[TCA_CAKE_INGRESS]);
+	}
+	if (tb[TCA_CAKE_ACK_FILTER] &&
+	    RTA_PAYLOAD(tb[TCA_CAKE_ACK_FILTER]) >= sizeof(__u32)) {
+		ack_filter = rta_getattr_u32(tb[TCA_CAKE_ACK_FILTER]);
+	}
+	if (tb[TCA_CAKE_ETHERNET] &&
+	    RTA_PAYLOAD(tb[TCA_CAKE_ETHERNET]) >= sizeof(__u32)) {
+		ethernet = rta_getattr_u32(tb[TCA_CAKE_ETHERNET]);
+	}
+	if (tb[TCA_CAKE_RTT] &&
+	    RTA_PAYLOAD(tb[TCA_CAKE_RTT]) >= sizeof(__u32)) {
+		interval = rta_getattr_u32(tb[TCA_CAKE_RTT]);
+	}
+
+	if (wash)
+		fprintf(f,"wash ");
+
+	if (ingress)
+		fprintf(f,"ingress ");
+
+	if (ack_filter == 0x0600)
+		fprintf(f,"ack-filter-aggressive ");
+	else if (ack_filter)
+		fprintf(f,"ack-filter ");
+
+	if (interval)
+		fprintf(f, "rtt %s ", sprint_time(interval, b2));
+
+	if (!atm && overhead == ethernet) {
+		fprintf(f, "raw ");
+	} else {
+		if (atm == 1)
+			fprintf(f, "atm ");
+		else if (atm == 2)
+			fprintf(f, "ptm ");
+		else
+			fprintf(f, "noatm ");
+
+		fprintf(f, "overhead %d ", overhead);
+
+		/* This is actually the *amount* of automatic compensation, but
+		 * we only report its presence as a boolean for now.
+		 */
+		if (ethernet)
+			fprintf(f, "via-ethernet ");
+	}
+
+	/* unconditionally report the overhead and hard_header_len overhead the
+	 * kernel added automatically
+	 */
+	fprintf(f, "total_overhead %d ", overhead);
+	fprintf(f, "hard_header_len %d ", ethernet);
+
+	if (mpu) {
+		fprintf(f, "mpu %d ", mpu);
+	}
+
+	if (memlimit)
+		fprintf(f, "memlimit %s", sprint_size(memlimit, b1));
+
+	return 0;
+}
+
+static int cake_print_xstats(struct qdisc_util *qu, FILE *f,
+			     struct rtattr *xstats)
+{
+	/* fq_codel stats format borrowed */
+	struct tc_fq_codel_xstats *st;
+	struct tc_cake_xstats     *stnc;
+	SPRINT_BUF(b1);
+	SPRINT_BUF(b2);
+
+	if (xstats == NULL)
+		return 0;
+
+	if (RTA_PAYLOAD(xstats) < sizeof(st->type))
+		return -1;
+
+	st   = RTA_DATA(xstats);
+	stnc = RTA_DATA(xstats);
+
+	if (st->type == TCA_FQ_CODEL_XSTATS_QDISC && RTA_PAYLOAD(xstats) >= sizeof(*st)) {
+		fprintf(f, "  maxpacket %u drop_overlimit %u new_flow_count %u ecn_mark %u",
+			st->qdisc_stats.maxpacket,
+			st->qdisc_stats.drop_overlimit,
+			st->qdisc_stats.new_flow_count,
+			st->qdisc_stats.ecn_mark);
+		fprintf(f, "\n  new_flows_len %u old_flows_len %u",
+			st->qdisc_stats.new_flows_len,
+			st->qdisc_stats.old_flows_len);
+	} else if (st->type == TCA_FQ_CODEL_XSTATS_CLASS && RTA_PAYLOAD(xstats) >= sizeof(*st)) {
+		fprintf(f, "  deficit %d count %u lastcount %u ldelay %s",
+			st->class_stats.deficit,
+			st->class_stats.count,
+			st->class_stats.lastcount,
+			sprint_time(st->class_stats.ldelay, b1));
+		if (st->class_stats.dropping) {
+			fprintf(f, " dropping");
+			if (st->class_stats.drop_next < 0)
+				fprintf(f, " drop_next -%s",
+					sprint_time(-st->class_stats.drop_next, b1));
+			else
+				fprintf(f, " drop_next %s",
+					sprint_time(st->class_stats.drop_next, b1));
+		}
+	} else if (stnc->version >= 1 && stnc->version < 0xFF
+				&& stnc->max_tins == TC_CAKE_MAX_TINS
+				&& RTA_PAYLOAD(xstats) >= offsetof(struct tc_cake_xstats, capacity_estimate))
+	{
+		int i;
+
+		if(stnc->version >= 3)
+			fprintf(f, " memory used: %s of %s\n", sprint_size(stnc->memory_used, b1), sprint_size(stnc->memory_limit, b2));
+
+		if(stnc->version >= 2)
+			fprintf(f, " capacity estimate: %s\n", sprint_rate(stnc->capacity_estimate, b1));
+
+		switch(stnc->tin_cnt) {
+		case 3:
+			fprintf(f, "                 Bulk   Best Effort      Voice\n");
+			break;
+
+		case 4:
+			fprintf(f, "                 Bulk   Best Effort      Video       Voice\n");
+			break;
+
+		case 5:
+			fprintf(f, "              Low Loss  Best Effort   Low Delay       Bulk  Net Control\n");
+			break;
+
+		default:
+			fprintf(f, "          ");
+			for(i=0; i < stnc->tin_cnt; i++)
+				fprintf(f, "       Tin %u", i);
+			fprintf(f, "\n");
+		};
+
+		fprintf(f, "  thresh  ");
+		for(i=0; i < stnc->tin_cnt; i++)
+			fprintf(f, "%12s", sprint_rate(stnc->threshold_rate[i], b1));
+		fprintf(f, "\n");
+
+		fprintf(f, "  target  ");
+		for(i=0; i < stnc->tin_cnt; i++)
+			fprintf(f, "%12s", sprint_time(stnc->target_us[i], b1));
+		fprintf(f, "\n");
+
+		fprintf(f, "  interval");
+		for(i=0; i < stnc->tin_cnt; i++)
+			fprintf(f, "%12s", sprint_time(stnc->interval_us[i], b1));
+		fprintf(f, "\n");
+
+		fprintf(f, "  pk_delay");
+		for(i=0; i < stnc->tin_cnt; i++)
+			fprintf(f, "%12s", sprint_time(stnc->peak_delay_us[i], b1));
+		fprintf(f, "\n");
+
+		fprintf(f, "  av_delay");
+		for(i=0; i < stnc->tin_cnt; i++)
+			fprintf(f, "%12s", sprint_time(stnc->avge_delay_us[i], b1));
+		fprintf(f, "\n");
+
+		fprintf(f, "  sp_delay");
+		for(i=0; i < stnc->tin_cnt; i++)
+			fprintf(f, "%12s", sprint_time(stnc->base_delay_us[i], b1));
+		fprintf(f, "\n");
+
+		fprintf(f, "  pkts    ");
+		for(i=0; i < stnc->tin_cnt; i++)
+			fprintf(f, "%12u", stnc->sent[i].packets);
+		fprintf(f, "\n");
+
+		fprintf(f, "  bytes   ");
+		for(i=0; i < stnc->tin_cnt; i++)
+			fprintf(f, "%12llu", stnc->sent[i].bytes);
+		fprintf(f, "\n");
+
+		fprintf(f, "  way_inds");
+		for(i=0; i < stnc->tin_cnt; i++)
+			fprintf(f, "%12u", stnc->way_indirect_hits[i]);
+		fprintf(f, "\n");
+
+		fprintf(f, "  way_miss");
+		for(i=0; i < stnc->tin_cnt; i++)
+			fprintf(f, "%12u", stnc->way_misses[i]);
+		fprintf(f, "\n");
+
+		fprintf(f, "  way_cols");
+		for(i=0; i < stnc->tin_cnt; i++)
+			fprintf(f, "%12u", stnc->way_collisions[i]);
+		fprintf(f, "\n");
+
+		fprintf(f, "  drops   ");
+		for(i=0; i < stnc->tin_cnt; i++)
+			fprintf(f, "%12u", stnc->dropped[i].packets);
+		fprintf(f, "\n");
+
+		fprintf(f, "  marks   ");
+		for(i=0; i < stnc->tin_cnt; i++)
+			fprintf(f, "%12u", stnc->ecn_marked[i].packets);
+		fprintf(f, "\n");
+
+		if(stnc->version >= 5) {
+			fprintf(f, "  ack_drop");
+			for(i=0; i < stnc->tin_cnt; i++)
+				fprintf(f, "%12u", stnc->ack_drops[i].packets);
+			fprintf(f, "\n");
+		}
+
+		fprintf(f, "  sp_flows");
+		for(i=0; i < stnc->tin_cnt; i++)
+			fprintf(f, "%12u", stnc->sparse_flows[i]);
+		fprintf(f, "\n");
+
+		fprintf(f, "  bk_flows");
+		for(i=0; i < stnc->tin_cnt; i++)
+			fprintf(f, "%12u", stnc->bulk_flows[i]);
+		fprintf(f, "\n");
+
+		if(stnc->version >= 4) {
+			fprintf(f, "  un_flows");
+			for(i=0; i < stnc->tin_cnt; i++)
+				fprintf(f, "%12u", stnc->unresponse_flows[i]);
+			fprintf(f, "\n");
+		}
+
+		fprintf(f, "  max_len ");
+		for(i=0; i < stnc->tin_cnt; i++)
+			fprintf(f, "%12u", stnc->max_skblen[i]);
+		fprintf(f, "\n");
+	} else {
+		return -1;
+	}
+	return 0;
+}
+
+struct qdisc_util cake_qdisc_util = {
+	.id		= "cake",
+	.parse_qopt	= cake_parse_opt,
+	.print_qopt	= cake_print_opt,
+	.print_xstats	= cake_print_xstats,
+};
-- 
2.7.4



More information about the Cake mailing list